Document watch-admin default behavior change in the v4-to-v5 migration guide

[pwizla]

This PR adds a note to the "Admin panel customization" section of the step-by-step migration guide to mention that `strapi develop` now runs in watch-admin mode by default in Strapi 5 (previously opt-in via `--watch-admin` in v4), and that `--no-watch-admin` can be used to disable it.

Reported in #3427.

Fixes #3427

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Project	Deployment	Actions	Updated (UTC)
documentation	Ready	Preview	Aug 31, 2026 7:55am

[t-fritsch]

thanks for the fix, shouldn't this be mentioned in /cms/migration/v4-to-v5/breaking-changes too ?

[pwizla]

Good catch, and you were right on both counts: watch-admin was not mentioned anywhere in the migration section, so the AI answer on the issue was wrong about it already being covered in the breaking changes page.

I have added a dedicated breaking change page, watch-admin-enabled-by-default, listed it in the breaking changes database under "Plugins, providers, admin panel and front-end customization", and pointed the step-by-step entry to it instead of the CLI reference, for consistency with the other entries in that list.

[t-fritsch]

thanks ! perfect 👌

[pwizla]

Now merging the PR 🚀
Thanks again for being very cautious about this, @t-fritsch, and for going the extra mile by creating the PR after reporting the feedback on the website 😊

[t-fritsch]

You're welcome, the button to create an issue shown just after the feedback submission is a great idea :)
thank you for replying so quickly !